VPS passwords are created at the time of VPS deployment. Passwords should be specific to each VPS and should NOT be your SkySilk account password. This password can only be changed from inside the virtual machine itself. If you forgot your virtual machine's password, you will need to reset it.
CHANGE A VPS Password on Linux
To change a VPS's password, first sign into the machine as root. Then type
(where user is the username for the password you are changing, in this case, most likely 'root'). The system will prompt you to enter a password. Passwords do not echo to the screen when you enter them (meaning, you won't see anything as you are typing, so remember where you are when typing your password, then press enter).
You can also change your own password, by typing
(without specifying a username). You will be prompted to enter your old password for verification, and then a new password.
If changing your password doesn't work, you can try to reset it: